Laboratory trials were carried out to observe the influence of the addition of increasing amounts of ammonium sulfate to the sugar cane juice and their effect on the alcoholic yield. The alcoholic yields improved when the addition of ammonium sulfate were increased from 0.25 up to 0.75 gr/liter then decreased for higher concentrations. The experiments showed that the highest alcoholic yields are obtained when the sugar cane juice of var. Co. 290 is enriched with ammonium sulfate on the basis of 0.75 gr/liter.